Effect of silica fume addition on the properties of whiteware compositions

The effect of silica fume (SF) addition as a substitution of quartz on the thermo-mechanical properties and microstructure of traditional whiteware body compositions was studied. Noticeable improvement (10.0+0.5%) in the mechanical strength was observed on replacing quartz by 10% silica fume in whiteware body with the reduction of maturing temperature by 50 °C whereas addition of 25% silica fume reduced by 100 °C. The increase in strength has been attributed to the decrease in true porosity of the material as well as to the reduction of free quartz content in the composition. 34% Reduction of percentage thermal expansion at 600 °C was measured in the body mix containing 25% silica fume replacing quartz matured at 1150 °C, compared to the reference body matured at 1250 °C. The lower maturing temperature of the body would be helpful to reduce the fuel consumption and thus reduce production costs.